Category Archives: Bristol

Biodiversity Net Gain Assessment for Equestrian Development in South Gloucestershire

Biodiversity Net Gain Assessment for Equestrian Development in South Gloucestershire

Project Overview and Location

Southwest Environmental Limited was commissioned by an individual to prepare a Biodiversity Net Gain (BNG) assessment for a proposed equestrian development in Charfield, South Gloucestershire. The site falls under the jurisdiction of the Stroud District Council planning authority. The proposed development involves the construction of a new horse stable block and the retention of a gravel access track. We completed this ecological reporting with a short lead time to meet the project schedule.

Two muscular chestnut horses frolic and gallop across a sunny summer field, with a third horse blurred in the distant wetland background.

Two energetic chestnut horses gallop and turn sharply through a sunlit summer pasture in France, showcasing their powerful builds as a third horse rests near the wetlands behind them.

Retrospective Baseline Assessment

The site is an established equestrian area historically used for grazing, primarily consisting of modified grassland, an artificial unvegetated wood chip paddock, and native hedgerows[cite: 26, 28]. A gravel access track had been installed across part of the modified grassland without prior planning permission, necessitating a retrospective analysis[cite: 26]. In accordance with Schedule 7A of the Town and Country Planning Act 1990 and statutory BNG guidance, the biodiversity baseline was established using the date of April 2025, which immediately preceded the unpermitted habitat degradation[cite: 26, 30]. By utilising historic satellite imagery alongside current site data, the pre-degradation baseline was calculated at 1.98 Habitat units and 1.20 Hedgerow units using the Statutory Biodiversity Metric 4.0[cite: 27, 35].

Habitat Enhancement and Mitigation Strategy

To achieve the mandatory minimum 10% net gain required for planning approval, a targeted landscape plan was developed focusing entirely on on-site interventions[cite: 27, 32, 35]. The plan mandates the enhancement of 700 square metres of modified grassland from a “Poor” condition baseline to “Moderate” condition other neutral grassland[cite: 32, 35]. This transition will be managed through a specified cutting regime and the introduction of native neutral grassland species to reduce nutrient status and competition[cite: 32]. Additionally, 70 metres of the existing native hedgerow will be enhanced from “Moderate” to “Good” condition using traditional management practices such as hedgelaying and gap planting with native species[cite: 32, 33, 35]. The strategy also includes the planting of four small native trees[cite: 33, 35].

Net Gain Achievements and Long-Term Management

The proposed habitat interventions adhere to the ten good practice principles for BNG, ensuring a measurable contribution to local ecology[cite: 31]. All new and enhanced habitats will be secured under a 30-year long-term management and monitoring plan[cite: 36]. Following the implementation of these measures, the site will deliver 2.20 Habitat units, generating an 11.31% net gain, and 1.33 Hedgerow units, generating a 10.86% net gain[cite: 35, 36]. This output completely satisfies the project’s trading rules and statutory net gain targets[cite: 35]. For further information regarding our ecological planning services, please visit Southwest Environmental Limited.

Please contact us if you would like a fixed price quotation.

Shadow Habitats Regulation Assessment for Residential Development in Wedmore, Somerset

Shadow Habitats Regulation Assessment for Residential Development in Wedmore, Somerset

Southwest Environmental Limited was commissioned by a planning consultancy to undertake a Shadow Habitats Regulation Assessment (SHRA) for a proposed development in Wedmore, Somerset. The project site is located within the planning jurisdiction of Somerset West and Taunton Council. The development involves the conversion of an existing residential dwelling into two separate residential properties. This comprehensive assessment was completed with a short lead time to ensure the applicant could proceed with their planning submission without delay.

High-angle view of stone cottages in Lower Burrow overlooking green farmland and flooded fields across West Moor on the Somerset Levels.

Overview of Lower Burrow and floodwaters on West Moor in the Somerset Levels.

Regulatory Context and Site Designations

The SHRA was prepared in strict compliance with the Conservation of Habitats and Species Regulations 2017 (as amended). The assessment is necessary under Regulation 63 to determine the potential effects of nutrient changes caused by the project on the River Axe and the Somerset Levels and Moors Ramsar site. The Ramsar site supports vulnerable ecological communities, including 17 species of Red Data Book aquatic invertebrates and rare vascular plants, making it highly sensitive to eutrophication and water chemistry changes

Nutrient Loading Assessment

Stage 1 Screening identified a potential impact pathway during the operational phase of the development Foul water from the proposed residential use would be discharged to public sewers, subsequently discharging via the Wedmore Water Recycling Centre (WRC) to tributaries of the River Axe.

In Stage 2 Appropriate Assessment, the Somerset Levels and Moors Phosphorous Budget Calculator was utilized to quantify the expected nutrient output. The calculation determined that, without mitigation, the development would result in a phosphorus loading of 0.22kg TP/yr (Post 2025), a figure that includes a 20% precautionary buffer. Any unmitigated increase in phosphorus could adversely affect the conservation objectives of the Ramsar site.

Mitigation and Nutrient Neutrality

To eliminate adverse effects on site integrity, mitigation measures were formally integrated into the project plan. The calculated budget of 0.22kg TP/year will be entirely offset through the purchase of Phosphorus Credits. The reservation of these credits will be secured as a pre-commencement condition, managed and monitored by Somerset County Council.

With this mitigation applied, the additional nutrient load from the development is reduced to zero, rendering the project entirely phosphorus neutral. The assessment concludes that the project will not adversely affect the integrity of the Somerset Levels and Moors Ramsar Site or the River Axe.

For more information on our environmental assessment capabilities and nutrient neutrality calculations, please visit our Habitats Regulations Assessment services page.

Please contact us if you would like a fixed price quotation.

Preliminary Ecological Appraisal – Yeovil, Somerset

Preliminary Ecological Appraisal for Proposed Agricultural Development in Somerset

Southwest Environmental Limited recently prepared a Preliminary Ecological Appraisal (PEA) report for a surveying firm in Yeovil, Somerset. The site is positioned within the planning jurisdiction of South Somerset District Council. The appraisal was commissioned in connection with the proposed development of a single farmworker’s dwelling and an associated parking area. Our team completed the necessary ecological surveying and reporting with a rapid turnaround.

Methodology and Scope of Works

The ecological appraisal was conducted in strict accordance with industry standards, incorporating the CIEEM Guidelines for Ecological Impact Assessment (2024). The assessment commenced with a desktop study to identify statutory designated sites, local habitats, and geo-spatially tagged species within the site’s zone of influence. The site is located inside the Site of Special Scientific Interest (SSSI) Impact Risk Zones of Influence for multiple biological sites, including Grove Farm and Whitevine Meadows. The desktop phase also verified that the site is located 1,155 metres north of the Dorset National Landscape, an Area of Outstanding Natural Beauty. Following the desktop review, a Phase 1 habitat survey was executed to classify and map the habitats present, adhering to the standard UK Habitat Classification (UKHab) system. Further details regarding our ecological assessments can be found on the Southwest Environmental Limited ecology page.

Habitat Classification and Species Assessment

The surveyed site predominantly consists of modified grassland, covering approximately 1,618 square metres, and is characterised by a short sward dominated by perennial ryegrass. The eastern and southern boundaries contain continuous sections of mixed scrub, measuring approximately 182 square metres, comprising species such as bramble, common nettle, field elm, and elder.

During the field survey, the site was systematically evaluated for its potential to support species protected under national legislation, including the Wildlife and Countryside Act 1981 (as amended), the Conservation of Habitats and Species Regulations 2017 (as amended), and the Natural Environment and Rural Communities (NERC) Act 2006. The assessment concluded that the mixed scrub boundaries offer suitable nesting habitat for common and widespread bird species Additionally, the site provides potential foraging and commuting habitats for mammals, such as hedgehogs, and various terrestrial invertebrates. The preliminary protected species assessment also investigated the potential for roosting bats; however, the absence of onsite trees, buildings, and suitable roosting features led to a low likelihood of roosting bats being present. Similarly, the site offers sub-optimal terrestrial habitat for great crested newts due to the lack of dense tussocky cover and aquatic breeding features.

Conclusions and Site Enhancements

The overall nature conservation value of the site was determined to be low. The proposed residential development is anticipated to have a minimal ecological impact, provided that specific precautionary mitigation measures are implemented prior to and during construction. These essential measures include the directional mowing of grassland to displace any potential reptiles and the scheduling of scrub clearance outside of the active bird nesting season, which typically occurs from March to September inclusive. Consequently, no further Phase 2 species-specific surveys were deemed necessary for this project.

The development presents actionable opportunities to enhance the site’s biodiversity. Recommendations include native hedgerow planting, the creation of log piles, the installation of bat and bird boxes, and the incorporation of permeable boundaries featuring hedgehog gaps in new fencing.

Please contact us if you would like a fixed price quotation.

How many BNG Credits per Acre?

How many BNG Credits per Acre?

If you are considering giving up some of you farm land for BNG credits, then of course you will need to know how many BNG credits you will get per acre. The land you are giving up for BNG will be out of use for many years and as such it is only right to investigate the returns you might expect.

BNG Credits are created by changing land from one use to another. For example a field to woodland, or some low lying meadows in to wetlands.

Not Just “How Many”

The first thing to realize is that it is not just a case of “how many”. As with wine or stamps the price of credits varies based on “distinctiveness“. Grassland may have quite low “distinctiveness”, whilst a lake would have very high distinctiveness. This can affect the price of each credit by 400%. (£40,000 to £200,000 or more).

Wetlands are a Very Good Option for BNG

But. How Many BNG Credits per Acre?

The short answer might be about 1 BNG Credit per Acre. Or 2 BNG Credits per Hectare.

This is based a few real world examples we have worked on where say 4 hectares of marginal land yielded around 7 BNG Credits.

But of course it is not that simple. The credits come from improvements in biodiversity. So if you start with good bio diversity (say scrub) then you will gain less when you “upgrade” to woodland.

Your best possible “yield” would be to upgrade mono-cultural farmland to something like a swamp or lake. But in terms of profit (especially in the long term) perhaps it is better to use scruffy marginal land and make fewer credits.

A last word. If you are think perhaps you could “tidy up” an area and then re-wild it in a year of two remember that what you do is all being recorded by satellites (google earth), and part of the process if proving that the land has not recently been changed.

Prices Can Vary Per Unit

Want to Know More

If you would like to know how much money you could make from BNG credits, then please do contact us (wt@southwest-environmental.co.uk) and we can arrange for our ecologist to advise you on the best way forward.